Radio frequency identification (RFID) systems have achieved wide popularity in a number of applications, as they provide a cost-effective way to track the location of a large number of items in real time. Most RFID systems includes two primary components: an RFID reader (also known as an interrogator or RFID reader device); and one or more RFID tags (also known as RFID transponders). The RFID reader generates or emits a radio-frequency (RF) interrogation signal (sometimes also called a polling signal). The RFID tag is a miniature device that is capable of responding to the RF interrogation signal by generating an RF response signal that is transmitted back to the RFID reader over an RF channel. The RF response signal is modulated in a manner that conveys identification data (i.e., a tag identifier (ID)) for the responding RFID tag back to the RFID reader. In large-scale applications, such as warehouses, retail spaces, and the like, many types of RFID tags may exist in the environment (or “site”). Likewise, multiple types of readers, such as RFID readers, active tag readers, 802.11 tag readers, Zigbee tag readers, etc., are typically used throughout the space, and may be linked by network controller or wireless switches and the like.
RFID systems are used in a number of different applications such as object tracking, security, inventory control/tracking in retail stores, warehouses, shipping centers, etc. For instance, in one inventory tracking application, some retails stores have begun using the RFID technology to track the location of items/inventory/articles/merchandise present in the store. In such applications, each item has an RFID tag attached to it so that the sales staff does not need to scan every item to check inventory, but rather can check items on a shelf using an RFID reader and/or receive an item inventory report. This generally saves time, but still involves human intervention.